Periodic Reporting for period 1 - JETSET (Launching, propagation and emission of relativistic jets from binary mergers and across mass scales)
Okres sprawozdawczy: 2021-10-01 do 2023-03-31
JETSET focuses on understanding the formation, propagation, and emission of relativistic jets originating from merging binary systems. It investigates whether similar physical processes are responsible for jet phenomena across a wide range of mass scales, from small black holes to supermassive ones. By studying electromagnetic radiation, neutrinos, and gravitational waves, JETSET is significantly advancing our knowledge of the fundamental nature of spacetime and the intricate dynamics of plasma under extreme conditions, shedding light on the underlying principles that govern our universe.
Further work performed by the JETSET team within WP1 includes a comprehensive study of fully general-relativistic hydrodynamics simulations of binary neutron stars using the V-QCD EOS, which incorporates the possibility of a quark phase appearing during the post-merger phase transition. This scenario could have significant implications for gravitational waves and the merger frequency. Additionally, using fully general-relativistic magnetohydrodynamics (GRMHD) simulations, we have investigated the role of the magnetic field in binary neutron star mergers, particularly in explaining mass ejection, jet launching, and the generation of short gamma-ray bursts. Our research explores the effects of turbulence and Kelvin-Helmholtz instabilities in the crust of neutron stars and the post-merger remnants. These latter study is very important to understand the formation channels of the large magnetic necessary to produce a relativistic jet in a GRB (WP2).
To gain a deeper understanding of particle acceleration within relativistic jets, we employed systematic particle-in-cell (PIC) numerical simulations to investigate the mechanisms behind particle acceleration and plasma heating at microscopic scales (WP1 and WP2). By updating the non-thermal electron and ion distribution functions, our results established a self-consistent connection between electron and proton temperatures, considering macroscopic plasma properties. Overall, our research efforts contribute to advancing the knowledge of jet dynamics in generic jets and shedding light on the processes of jet formation, propagation, and particle acceleration across the mass scale (WP4).
Finally, we analysed the jet dynamics in the M87 galaxy, specifically focusing on the active galactic nuclei, M87*, performing general-relativistic GRMHD simulations to explore the launching and propagation of the jet around a rotating supermassive black hole. We investigated the influence of the accretion disc model and magnetic field morphology, electron temperature, electron distribution function, and black hole rotation (WP1). In addition, we carried out general relativistic radiative transfer (GRRT) calculations to examine the multi-frequency electromagnetic emission. We tested theoretical models and compared them to observations in terms of their morphological features and across their wide electromagnetic spectrum (WP2 and WP5).
By the end of the project, the JETSET team aims to significantly enhance our understanding of magnetised jet structures across different scales, including both stellar-mass systems relevant for GRBs and AGNs. In both scenarios, we will employ a vast suite of newly developed numerical tools to investigate jet launching dynamics exploring the effects of the equation of state, a self-consistent treatment of neutrino radiation, spacetime evolution, the extraction of energy from the accretion process and the subsequent dissipation of electromagnetic energy through magnetic reconnection. In this way, we seek to unravel the fundamental mechanisms that govern the formation, propagation, and energy dissipation of these jets.